Cloudflare’s Rocket Loader

Rocket Loader from Cloudflare is calling in the JavaScript files after everything else has been loaded, but because of this a lot of JavaScript events are skipped, which are used by many JavaScript developers, so complex codes like ours aren't working with it, and you shouldn't use it.

But according to this article the loaded scripts can be ignored by giving data-cfasync="false" to them. First of all, you should update your slider to version 3.0.36 or newer, then find the Script attributes option at the Global settings, and write this code there: